This invention relates to an apparatus for producing a lap for a carding machine or roller card wherein a feed chute for depositing the fiber tufts is disposed upstream of the machine, wherein the fiber tufts are fed into the feed chute from the top and are discharged therefrom at the bottom and wherein a stream of air enters the feed chute and leaves it through air exit openings provided on the front and/or rear wall of the feed chute.
It is known that laps of different height (thickness) can be produced by displacing one or both (front and rear) vertical walls of the feed chute to thus change the depth thereof. With such a device, however, the lap thickness only along the entire lap width can be varied.